Closed-circuit-tv-x-ray microscope

ABSTRACT

Closed-circuit TV fluoroscopic equipment, such as X-ray microscopes of reduced physical size and improved performance, in which X-ray source is enclosed in shielding capsule and a shielding chamber containing object to be X-rayed is positioned on an X-ray beam intercept path relative to a signal converter for adjustment of X-ray intensity and object-to-target distance.

United States Patent Rabodzei et al.

I 1 Jan. 14, 1975 I 1 CLOSED-CIRCUlT-TV-X-RAY MICROSCOPE I76] inventors: Nikolai Vasilievich Rabodzei,

lnstitutskaya ulitsa, 6-a, kv. 39; Vladimir Alexandrovich Astrin, lnstitutskaya ulitsa, l2, kv. l9; Nina Vasilievna Kuzmicheva,

lnstitutskaya ulitsa, 21, kv.- 31; Gennady Vladimirovich Shidlovsky, Tscntralnaya ulitsa, 2-a, kv. 56; Evgeny Mikhailovich Ljubimov, ulitsa Tsentralnaya, l9, kv. 12; Mikhail Nikolaevich Nadobnikov, ulitsa Voxalnaya, 21, kv. 7, all of Fryazino Moskovskoi Oblasti, U.S.S.R.

22 Filed: June29, 1970 21 Appl. No.: 50,431

[52] U.S. Cl 250/358, 250/363, 250/490,

250/491 [51] Int. Cl. G0ln 23/00 Field of Search 250/495 A, 49.5 B, 49.5 E, 250/495 PE, 51.5, 53, 65, 71, 71.5, 213 VT; 178/68, DIG. l, DIG. 5

[56] References Cited UNITED STATES PATENTS 2,814,729 11/1957 Newberry et al. 250/495 A OTHER PUBLICATIONS Cosslett et al., X-ray Microscopy And Microradiography, Academic Press, lnc., Newv York, 1957, p. 371.

Primary ExaminerWilliam F. Lindquist Attorney, Agent, or Firm-Waters, Roditi, Schwartz &

Nissen [57] ABSTRACT Closed-circuit TV fluoroscopic equipment, such as X-ray microscopes of reduced physical size and improved performance, in which X-ray source is enclosed in shielding capsule and a shielding chamber containing object to be X-rayed is positioned on an X-ray beam intercept path relative to a signal converter for adjustment of X-ray intensity and object-totarget distance.

1 Claim, 1 Drawing Figure CLOSED-CIRCUlT-TV-X-RAY MICROSCOPE The present invention relates to closed-circuit-TV fluoroscopic equipment with magnification (closedcircuit-TV X-ray microscopes) and is intended for direct observation in a magnified form of the internal structure of opaque objects on a TV screen and also for a variety of studies of opaque objects, mainly for the non-destructive detection of hidden microscopic defects in various electronic devices.

Broadly known in the art are closed-circuit-TV X-ray microscopes which have a shielding capsule enclosing an X-ray source, and an object chamber in which the path of x-rays is consecutively intercepted by the object being viewed and a converter of X-ray shadow images into TV signals. An enlarged image of the internal structure of the object appears on the screen of a closed-circuit TV monitor which is electrically connected to the X-ray to TV signal converter.

The actual position of the object being X-rayed can be verified through an inspection window in the object chamber while the displacement of the object relative to the target of the signal converter and the X-ray source is effected by a variety of mechanism, fixtures and manipulators.

The basic performance characteristics of a closedcircuit-TV X-ray microscope, such as the resolution, the contrast sensitivity and the range of thicknesses that can'be examined are all governed by the amount of X-rays reaching the object andas a shadow image the target of the X-ray to TV signal converter. Since existing X-ray tubes provide for the adjustment of X-ray dose within narrow limits only, the gap is usually bridged by varying the distance from the converter target to the X-ray tube. In existing types of closed-circuit- TV X-ray microscopes this is done by moving the X-ray tube towards the converter.

Such a design suffers from a number of disadvantages such as the complexity and unwieldiness of the mechanisms effecting the displacement of the X-ray tube and, as a consequence, the considerable size of the entire closed-circuit-TV Xray microscope.

It is the object of the present invention to simplify the dose-adjustment system in such a way that with the same useful volume of the object chamber it will be possible to reduce the size of the entire closed-circuit- TV X-ray microscope and to make it more convenient to use and service.

With these and other objects in view, in a closedcircuit-TV X-ray microscope incorporating an X-ray source enclosed in a shielding capsule and a shielding object chamber inside which the object to be X-rayed is placed so that it intercepts the.beam of X-rays before thay reach the target of an X-ray to TV-signal converter, the said converter is, according to the invention, placed in an enclosure attached to the object chamber so that there is a possibility for controlled displacement along the beam of X-rays into the object chamber for adjustment of X-ray dose and of the object-to-target distance. It is preferable to have the converter permanently attached to the enclosure which can be moved into the object chamber.

In order to have a wider range of dose adjustment, it is advisable to use a sharp-focused X-ray tube located close to the object chamber and of a converter which can be moved for nearly all depth of the object chamber, so that the distance between the X-ray tube and the converter target can be varied by a factor of 2.5-3.

The embodiment of a closed-circuit-TV X-ray microscope in accordance with the present invention offers the following advantages.

The placement of the converter outside the object chamber in a separate enclosure has increased the volume which can be used for manipulations of large-size objects and has reduced the overall dimensions of the microscope as a whole owing to the reduction of the space occupied by the chamber and required for the movement of the X-ray tube.

The manipulation of the object in the course of X- raying has been considerably simplified, for, according to the invention, instead of moving the object to the converter target by a suitable mechanism, the converter itself is moved inside the object chamber until the object to be X-rayed is in the requisite position.

The invention will be best understood by reference to the description of a preferred embodiment when read in connection with the accompanying drawing which shows a cross-sectional sketch of a closed-circuit-TV X-ray microscope, according to the invention, with a converter movable inside the object chamber.

Referring to the drawing, there is a closed-circuit-TV X-ray microscope having an object chamber 1 and a shielding capsule 2 which holds an X-ray source 3.

The object chamber 1 is permanently attached to the capsule 2. The wall of the object chamber 1, adjacent to the capsule, has a port 4 to pass X-rays, while in the side wall there is an inspection window 5 to watch the position of an object 6 being X-rayed and a target 7 of a converter 8 of shadow X-ray images into TV signals.

X-rays, on passing through the object 6, form a shadow X-ray image of the object on the target 7. The converter 8 is permanently mounted in an enclosure 9 attached to the object chamber 1. The position of the converter 8 relative to the X-ray source 3 can be adjusted by shifting the enclosure 9 into the object chamber, for which purpose there is a rack-and-screw movement (omitted in the drawing). In this way, the converter may be shifted to any position between the extreme ones (I and II, respectively, in FIG. 1).

Thus embodied, the microscope provides for an increase of ten times in the dose of X-rays reaching the object.

What is claimed is:

l. A closed-circuit-TV X-ray microscope, comprising; an X-ray source; a shielding capsule containing said X-ray source; a shielding object chamber having a common wall with said shielding capsule; an aperture in said wall for passing an X-ray beam from said X-ray source into said shielding object chamber; a converter for converting X-ray shadow images of an object located between said source and said converter into TV signals, said X-ray-TV converter and said object adapted to be positioned in said object chamber in the path of the X-ray beam and being movable along the axis thereof; and an enclosure permanently connected to said object chamber and extending through an aperture therein, said X-ray-TV converter being rigidly supported within said enclosure, said enclosure and the X- ray-TV converter supported therein being jointly movable through said aperture into said object chamber. 

1. A closed-circuit-TV X-ray microscope, comprising; an X-ray source; a shielding capsule containing said X-ray source; a shielding object chamber having a common wall with said shielding capsule; an aperture in said wall for passing an X-ray beam from said X-ray source into said shielding object chamber; a converter for converting X-ray shadow images of an object located between said source and said converter into TV signals, said X-ray-TV converter and said object adapted to be positioned in said object chamber in the path of the X-ray beam and being movable along the axis thereof; and an enclosure permanently connected To said object chamber and extending through an aperture therein, said X-ray-TV converter being rigidly supported within said enclosure, said enclosure and the X-ray-TV converter supported therein being jointly movable through said aperture into said object chamber. 